class_docstr: Iterator
code: def test_examples(
      self,
  ):
      for idx in self.test_idx:
          yield idx
  
imports: import os
  import tqdm
  import yaml
  import pgl
  import time
  import copy
  import numpy
  import os.path
  from pgl.utils.logger import log
  from pgl.graph import Graph
  from pgl import graph_kernel
  from pgl.sampling.custom import subgraph
  from ogb.lsc import MAG240MDataset, MAG240MEvaluator
  from dataset.base_dataset import BaseDataGenerator
  import time
label_desc: Use image node_id 5 for calling the MAG240M obj's underlying member method code with example usage: obj.test_examples() without return types